Centering device for lathes



sept. 29, 1931. I E, N BRODEN h 1,824,769

CENTERIG DEVICE FOR LATHES Sept. 29, 1931. E. N. BRODEN 1,824,769

CENTERING DEVICE FOR LATHES Filed Jan. 9, 1930 ZSheetS-Sheet 2 'AT1-SRP!EH:

Patented sept. 29, 1931 EDWIN NATANAEL BRODEN, 011*noXnpnY,Massaeirpsnrfrsl CENTERING Davies non LArrrrss 'Applicationfiled January 9,'1930. Serial Nm 419,667.

My invention relates to improvements in centering device for lathes andmore especially for jewellers lathes, andthe objects of my improvementsare, first, to provide a device to hold the spotter and, second, adevice for lifting the spotter away from the work dur'- ing operation ofdrilling.

I attain these objects by the mechanism illustrated in the accompanyingdrawings, in

Fig. 1 is a side view of my centering device shown in position forcentering or spotting the Work. K

Fig. 2 is a side view showing my'centering i5 device with the spotterarm raised and out oi' the way of the work.

Fig. 3 is a plan view of Fig. V1. l

Fig. 4 is a front view of the spotter arm, showing the spotter affixedto same.

n F ig. 5 is a side view of the spotter` arm showing the slot for springadjustment.' Fig. 6 is a side view of the spotter. Similar numeralsrefer to similar parts throughout the several views. l j

1 is the tail stock of a lathe carrying a slidable spindle, 2 is thespindle attached to drill chuck 3, 31 is the drill. On'the end ofspindleA 2 is loosely pivoteda lever 4, to one end of said lever 4 isa'loosely pivoted arm im 5, this arm is pivotally connected'toa'projection 6 on tail stock.

On the top of tail stock or.` spindle carrier is attached a latch orcatch 7, this latch is tached to the spindle carrier, on the front endof latch 7 and on top is a hook 9. n

The underside is a cutaway portion 10, this cutaway portion lOforms aprojection. This latch 7 is loosely pivoted at 11, and on the 40 rearend of latch 7 is an outwardly turned projection 12. On the arm 8 isalso a pro,- jection 13, this projectiony has a screw attachment 14whichregulates the movement of the arm 7. On arm 7 4isaliiXed'a spring15,one arm attached to arm 7,. and the other end attached to aprojection 151 on the tail stock 1. This spring 15 holds thearm 7 inposition. On the spindle2, and rigidly att-ached to the rearof drillchuck Vis anarm r n l c 90 16, on this arm 16 1s fastened an angle ironsupported and heldin place by an arm 8, at.

.Y is up.

,the front en d of, which .acts as;a.sup,port ,fori the spotterarn1i118. This Lsptter .anni

islslottechat 19V toallo'w movenientof said arm 18. This movement iscontrolled bya spring 20, which surrounds spotter arm 18.

On this slotted spotter arm 18 is a pivot 21, this pivot extends on eachside of said arm, the inner end to hold spring 20 in place, and theoutward end runs through a slot 22 on an arm 23 which is pivoted to arm16, and on one end of this arm is a projecting piece 24. 25 is the headof spotter arm 18, the head holds the spotter' 26 in place by a setscrew 27. 28 is the work clutch and 29 the work to be drilled. Inoperating my centering device, it is moved forward as in Fig. 1. Thisshows in position ready'to be spotted or centered. lThe spotter arm18`is then moved back by lever 4 until the projection. 24 on arm 23comes in contact with the'cutaway portion 10 on arm 7. ThisVoperationthrows the spotter arm up as in'F ig. 2 ofthe drawings andaway from the work which is now readyA to be drilled; To release spotterarm and bring it down to position for spotting or cenj tering, thisdevice is moved back by lever 4 vuntil the projection 24 on arm 23 comesin contactrwith catch 9which releases the spotter arm. The projection 24after the arm is lifted stays under the shoulder 10'until the spindle ismoved towards the left.` The arm 18 cannot godown because theprojection' 24 on arm 18 does not catch on to the hook 9 on the frontend of latch. 7 until the next backward movement to the right, when thehook 9 is dropped down, a slot 11 in latch 7 allows it to drop. In Fig.2`the projection 24 on arm 18 is not on the same level as in Fig. 1, lit is raised up, that is the reason the arm 18 The projection 24 on arm18 hooks ontol the hook 9 ifmoved to the right.

Heretofore the spotter 26 was placed on and also taken off the work tobe spotted by hand.4 v

Having now fully described my invention, what I claim is :-f y

In a device of the 'class described, a tail stock support, a tail stockspindle slidably mounted therein, means for sliding-saidspinim dle7 achuck at one end of said spindle, an anl,gle piece near the other end ofspindle, a latch loosely pivoted to said angle pieces, aspring Vforurging said latch in one direct1on,van

angle piece near the forward end of the spindle ad] aoent to the chuckand having a transverse pivot, a spotter arm having alongirtudinalslot-mounted on said pivot, a lever pivotally mounted onthe angle piece and having a longitudinal slot at its forward end and arearwardlvV projecting portion having a catch to be engaged Vby thelatch when the' spindle is moved rearwardly, a perforated plate slidablymounted on the spotter arm and having a pin to .engage the slot in thevlever and a spring interposed between 'said plate and the secondmentioned an le piece.

'Y EDWIN NATANAEL BR DEN.l

